Policy provisioning at a user equipment (UE)

ABSTRACT

Aspects of the disclosure relate to a method of operating a user equipment for wireless communication with a network. In some aspects, the UE establishes a connection to a network and obtains a control plane message from the network. The control plane message may include one or more types of policy information if a size of the one or more types of policy information is less than or equal to a maximum payload size of the control plane message, or information indicating at least a network location from where the one or more types of policy information may be obtained by the UE over a user plane if the size of the one or more types of policy information is greater than the maximum payload size of the control plane message, or a combination thereof. Other aspects, embodiments, and features are also claimed and described.

CROSS-REFERENCE TO RELATED APPLICATIONS

This application is a continuation application of U.S. patentapplication Ser. No. 16/158,206, entitled “POLICY PROVISIONING AT A USEREQUIPMENT (UE),” filed on Oct. 11, 2018, which claims priority to andthe benefit of U.S. Provisional Patent Application No. 62/572,524,entitled “POLICY PROVISIONING AT THE UE IN 5G SYSTEM,” filed on Oct. 15,2017, the entire contents of which are incorporated herein by referenceas if fully set forth below in their entireties and for all applicablepurposes.

TECHNICAL FIELD

The technology discussed below relates generally to wirelesscommunication systems, and more particularly, for policy provisioning ata user equipment (UE).

INTRODUCTION

In wireless communication systems, the network may control the behaviorof user equipments (UEs) using various types of policy information. Forexample, the network may define a route selection policy (also referredto as a UE route selection policy (URSP)) for the UE and the UE mayapply the URSP to determine how to route outgoing traffic (e.g., to anexisting protocol data unit (PDU) session or to a new PDU session). Insome scenarios, for example, the network may need to update suchpolicies being implemented by the UE due to changing network conditionsor to improve UE performance. However, in some circumstances,conventional approaches for delivering such updated policy informationto the UE may not be adequate or efficient.

BRIEF SUMMARY OF SOME EXAMPLES

The following presents a simplified summary of one or more aspects ofthe present disclosure, in order to provide a basic understanding ofsuch aspects. This summary is not an extensive overview of allcontemplated features of the disclosure, and is intended neither toidentify key or critical elements of all aspects of the disclosure norto delineate the scope of any or all aspects of the disclosure. Its solepurpose is to present some concepts of one or more aspects of thedisclosure in a simplified form as a prelude to the more detaileddescription that is presented later.

In one example, a method for wireless communication is disclosed. Themethod may be performed by a user equipment (UE). The method includesestablishing a connection to a network and obtaining a control planemessage from the network. The control plane message may include one ormore types of policy information if a size of the one or more types ofpolicy information is less than or equal to a maximum payload size ofthe control plane message, or information indicating at least a networklocation from where the one or more types of policy information may beobtained by the UE over a user plane if the size of the one or moretypes of policy information is greater than the maximum payload size ofthe control plane message.

In one example, an apparatus (e.g., a UE) for wireless communicationwith a network is disclosed. The apparatus includes a processor, atransceiver communicatively coupled to the processor, and a memorycommunicatively coupled to the processor. The processor may beconfigured to establish a connection to the network and obtain a controlplane message from the network. The control plane message may includeone or more types of policy information if a size of the one or moretypes of policy information is less than or equal to a maximum payloadsize of the control plane message, or information indicating at least anetwork location from where the one or more types of policy informationmay be obtained by the apparatus over a user plane if the size of theone or more types of policy information is greater than the maximumpayload size of the control plane message.

In one example, an apparatus (e.g., a UE) for wireless communicationwith a network is disclosed. The apparatus includes means forestablishing a connection to a network and means for obtaining a controlplane message from the network. The control plane message may includeone or more types of policy information if a size of the one or moretypes of policy information is less than or equal to a maximum payloadsize of the control plane message, or information indicating at least anetwork location from where the one or more types of policy informationmay be obtained by the apparatus over a user plane if the size of theone or more types of policy information is greater than the maximumpayload size of the control plane message.

In one example, a non-transitory computer-readable medium storingcomputer-executable code is disclosed. The non-transitorycomputer-readable medium may include code for causing a computer toestablish a connection to the network and to obtain a control planemessage from the network. The control plane message may include one ormore types of policy information if a size of the one or more types ofpolicy information is less than or equal to a maximum payload size ofthe control plane message, or information indicating at least a networklocation from where the one or more types of policy information may beobtained by the apparatus over a user plane if the size of the one ormore types of policy information is greater than the maximum payloadsize of the control plane message.

In one example a method for wireless communication is disclosed. Themethod may be performed by a UE. The method includes establishing aconnection to a server based on a network location preconfigured at theUE, obtaining one or more types of policy information from the server;and updating at least one policy based on the obtained one or more typesof policy information.

In one example, an apparatus (e.g., a UE) for wireless communicationwith a network is disclosed. The apparatus includes a processor, atransceiver communicatively coupled to the processor, and a memorycommunicatively coupled to the processor. The processor may beconfigured to establish a connection to a server based on a networklocation preconfigured at the apparatus, obtain one or more types ofpolicy information from the server, and update at least one policy basedon the obtained one or more types of policy information.

In one example, an apparatus (e.g., a UE) for wireless communicationwith a network is disclosed. The apparatus includes means forestablishing a connection to a server based on a network locationpreconfigured at the apparatus, means for obtaining one or more types ofpolicy information from the server, and means for updating at least onepolicy based on the obtained one or more types of policy information.

In one example, a non-transitory computer-readable medium storingcomputer-executable code is disclosed. The non-transitorycomputer-readable medium may include code for causing a computer toestablish a connection to a server based on a network locationpreconfigured at the apparatus, obtain one or more types of policyinformation from the server, and update at least one policy based on theobtained one or more types of policy information.

In one example, a method for wireless communication is disclosed. Themethod may be performed by a core network device (e.g., a server)configured to implement a policy control function. The method includesestablishing a connection with a user equipment (UE), and transmitting,to the UE, a control plane message. The control plane message mayinclude one or more types of policy information if a size of the one ormore types of policy information is less than or equal to a maximumpayload size of the control plane message, or information indicating atleast a network location from where the one or more types of policyinformation may be obtained by the UE over a user plane if the size ofthe one or more types of policy information is greater than the maximumpayload size of the control plane message.

In one example, an apparatus for wireless communication with a networkis disclosed. For example, the apparatus may be a core network device(e.g., a server) configured to implement a policy control function. Theapparatus includes a processor, a transceiver communicatively coupled tothe processor, and a memory communicatively coupled to the processor.The processor may be configured to establish a connection with a UE, andtransmit, to the UE, a control plane message. The control plane messagemay include one or more types of policy information if a size of the oneor more types of policy information is less than or equal to a maximumpayload size of the control plane message, or information indicating atleast a network location from where the one or more types of policyinformation may be obtained by the UE over a user plane if the size ofthe one or more types of policy information is greater than the maximumpayload size of the control plane message.

In one example, an apparatus for wireless communication with a networkis disclosed. For example, the apparatus may be a core network device(e.g., a server) configured to implement a policy control function. Theapparatus includes means for establishing a connection with a UE, andmeans for transmitting, to the UE, a control plane message. The controlplane message may include one or more types of policy information if asize of the one or more types of policy information is less than orequal to a maximum payload size of the control plane message, orinformation indicating at least a network location from where the one ormore types of policy information may be obtained by the UE over a userplane if the size of the one or more types of policy information isgreater than the maximum payload size of the control plane message.

In one example, a non-transitory computer-readable medium storingcomputer-executable code is disclosed. The non-transitorycomputer-readable medium may include code for causing a computer toestablish a connection with a UE, and transmit, to the UE, a controlplane message. The control plane message may include one or more typesof policy information if a size of the one or more types of policyinformation is less than or equal to a maximum payload size of thecontrol plane message, or information indicating at least a networklocation from where the one or more types of policy information may beobtained by the UE over a user plane if the size of the one or moretypes of policy information is greater than the maximum payload size ofthe control plane message.

These and other aspects of the invention will become more fullyunderstood upon a review of the detailed description, which follows.Other aspects, features, and embodiments of the present invention willbecome apparent to those of ordinary skill in the art, upon reviewingthe following description of specific, exemplary embodiments of thepresent invention in conjunction with the accompanying figures. Whilefeatures of the present invention may be discussed relative to certainembodiments and figures below, all embodiments of the present inventioncan include one or more of the advantageous features discussed herein.In other words, while one or more embodiments may be discussed as havingcertain advantageous features, one or more of such features may also beused in accordance with the various embodiments of the inventiondiscussed herein. In similar fashion, while exemplary embodiments may bediscussed below as device, system, or method embodiments it should beunderstood that such exemplary embodiments can be implemented in variousdevices, systems, and methods.

BRIEF DESCRIPTION OF THE DRAWINGS

FIG. 1 is a schematic illustration of a wireless communication system.

FIG. 2 is a conceptual illustration of an example of a radio accessnetwork.

FIG. 3 is a block diagram conceptually illustrating an example of ahardware implementation for a core network device according to someaspects of the disclosure.

FIG. 4 is a block diagram conceptually illustrating an example of ahardware implementation for a user equipment (UE) according to someaspects of the disclosure.

FIG. 5 illustrates an example of a potential 5G system architecture inservice-based interface representation for a non-roaming scenario inaccordance with various aspects of the disclosure.

FIG. 6 illustrates an example of a potential 5G system architecture inservice-based interface representation for a roaming scenario inaccordance with various aspects of the disclosure.

FIG. 7 illustrates an example of a potential 5G system architecture 700in a reference point representation for a roaming scenario in accordancewith various aspects of the disclosure.

FIG. 8 illustrates an exemplary table listing several types of policyinformation that may be delivered to a user equipment (UE) in accordancewith various aspects of the disclosure.

FIG. 9 illustrates an example of a downlink (DL) NAS transport messagefor delivering policy information.

FIG. 10 illustrates an example payload information IE structure that maybe used to update one or more policies at the UE.

FIG. 11 illustrates an example coding of payload information type bitsfor a payload information IE structure.

FIG. 12 illustrates an example coding of policy type bits for a payloadinformation IE structure.

FIG. 13 illustrates an example coding of download type bits for apayload information IE structure.

FIG. 14 (including FIGS. 14A to 14D) is a flow chart illustrating anexemplary process for steering a UE in a visited public land mobilenetwork (VPLMN) according to some aspects of the disclosure.

FIG. 15 is a flow chart illustrating an exemplary process for operatinga UE according to some aspects of the disclosure.

FIG. 16 is a flow chart illustrating an exemplary process for operatinga UE according to some aspects of the disclosure.

FIG. 17 is a flow chart illustrating an exemplary process for operatinga core network device according to some aspects of the disclosure.

DETAILED DESCRIPTION

The detailed description set forth below in connection with the appendeddrawings is intended as a description of various configurations and isnot intended to represent the only configurations in which the conceptsdescribed herein may be practiced. The detailed description includesspecific details for the purpose of providing a thorough understandingof various concepts. However, it will be apparent to those skilled inthe art that these concepts may be practiced without these specificdetails. In some instances, well known structures and components areshown in block diagram form in order to avoid obscuring such concepts.

While aspects and embodiments are described in this application byillustration to some examples, those skilled in the art will understandthat additional implementations and use cases may come about in manydifferent arrangements and scenarios. Innovations described herein maybe implemented across many differing platform types, devices, systems,shapes, sizes, packaging arrangements. For example, embodiments and/oruses may come about via integrated chip embodiments and othernon-module-component based devices (e.g., end-user devices, vehicles,communication devices, computing devices, industrial equipment,retail/purchasing devices, medical devices, AI-enabled devices, etc.).While some examples may or may not be specifically directed to use casesor applications, a wide assortment of applicability of describedinnovations may occur. Implementations may range a spectrum fromchip-level or modular components to non-modular, non-chip-levelimplementations and further to aggregate, distributed, or OEM devices orsystems incorporating one or more aspects of the described innovations.In some practical settings, devices incorporating described aspects andfeatures may also necessarily include additional components and featuresfor implementation and practice of claimed and described embodiments.For example, transmission and reception of wireless signals necessarilyincludes a number of components for analog and digital purposes (e.g.,hardware components including antenna, RF-chains, power amplifiers,modulators, buffer, processor(s), interleaver, adders/summers, etc.). Itis intended that innovations described herein may be practiced in a widevariety of devices, chip-level components, systems, distributedarrangements, end-user devices, etc. of varying sizes, shapes andconstitution.

A radio access technology (RAT) may, for example, correspond to a typeof technology or communication standard that may be utilized for radioaccess and communication over a wireless air interface. Just a fewexamples of RATs include GSM, UTRA, E-UTRA (LTE), Bluetooth, and Wi-Fi.The term new radio (NR) may generally refer to the new radio accesstechnology (e.g., 5G technology) undergoing definition andstandardization by 3GPP in Release 15.

The term access stratum may, for example, generally refer to afunctional grouping consisting of the parts in the radio access networkand in the UE, and the protocols between these parts being specific tothe access technique (i.e., the way the specific physical media betweenthe UE and the radio access network is used to carry information). Theterm non-access stratum (NAS) may, for example, generally refer toprotocols between the UE and the core network that are not terminated inthe radio access network.

The term quality of service (QoS) may, for example, generally refer to acollective effect of service performances which determine the degree ofsatisfaction of a user of a service. QoS may be characterized by thecombined aspects of performance factors applicable to all services, suchas: service operability performance; service accessibility performance;service retainability performance; service integrity performance; andother factors specific to each service.

The various concepts presented throughout this disclosure may beimplemented across a broad variety of telecommunication systems, networkarchitectures, and communication standards. Referring now to FIG. 1, asan illustrative example without limitation, various aspects of thepresent disclosure are illustrated with reference to a wirelesscommunication system 100. The wireless communication system 100 includesthree interacting domains: a core network 102, a radio access network(RAN) 104, and a user equipment (UE) 106. By virtue of the wirelesscommunication system 100, the UE 106 may be enabled to carry out datacommunication with an external data network 110, such as (but notlimited to) the Internet.

The RAN 104 may implement any suitable wireless communication technologyor technologies to provide radio access to the UE 106. As one example,the RAN 104 may operate according to 3^(rd) Generation PartnershipProject (3GPP) New Radio (NR) specifications, often referred to as 5G.As another example, the RAN 104 may operate under a hybrid of 5G NR andEvolved Universal Terrestrial Radio Access Network (eUTRAN) standards,often referred to as LTE. The 3GPP refers to this hybrid RAN as anext-generation RAN, or NG-RAN. Of course, many other examples may beutilized within the scope of the present disclosure.

As illustrated, the RAN 104 includes a plurality of base stations 108.Broadly, a base station is a network element in a radio access networkresponsible for radio transmission and reception in one or more cells toor from a UE. In different technologies, standards, or contexts, a basestation may variously be referred to by those skilled in the art as abase transceiver station (BTS), a radio base station, a radiotransceiver, a transceiver function, a basic service set (BSS), anextended service set (ESS), an access point (AP), a Node B (NB), aneNode B (eNB), a gNode B (gNB), or some other suitable terminology.

The radio access network 104 is further illustrated supporting wirelesscommunication for multiple mobile apparatuses. A mobile apparatus may bereferred to as user equipment (UE) in 3GPP standards, but may also bereferred to by those skilled in the art as a mobile station (MS), asubscriber station, a mobile unit, a subscriber unit, a wireless unit, aremote unit, a mobile device, a wireless device, a wirelesscommunications device, a remote device, a mobile subscriber station, anaccess terminal (AT), a mobile terminal, a wireless terminal, a remoteterminal, a handset, a terminal, a user agent, a mobile client, aclient, or some other suitable terminology. A UE may be an apparatusthat provides a user with access to network services.

Within the present document, a “mobile” apparatus need not necessarilyhave a capability to move, and may be stationary. The term mobileapparatus or mobile device broadly refers to a diverse array of devicesand technologies. UEs may include a number of hardware structuralcomponents sized, shaped, and arranged to help in communication; suchcomponents can include antennas, antenna arrays, RF chains, amplifiers,one or more processors, etc. electrically coupled to each other. Forexample, some non-limiting examples of a mobile apparatus include amobile, a cellular (cell) phone, a smart phone, a session initiationprotocol (SIP) phone, a laptop, a personal computer (PC), a notebook, anetbook, a smartbook, a tablet, a personal digital assistant (PDA), anda broad array of embedded systems, e.g., corresponding to an “Internetof things” (IoT). A mobile apparatus may additionally be an automotiveor other transportation vehicle, a remote sensor or actuator, a robot orrobotics device, a satellite radio, a global positioning system (GPS)device, an object tracking device, a drone, a multi-copter, aquad-copter, a remote control device, a consumer and/or wearable device,such as eyewear, a wearable camera, a virtual reality device, a smartwatch, a health or fitness tracker, a digital audio player (e.g., MP3player), a camera, a game console, etc. A mobile apparatus mayadditionally be a digital home or smart home device such as a homeaudio, video, and/or multimedia device, an appliance, a vending machine,intelligent lighting, a home security system, a smart meter, etc. Amobile apparatus may additionally be a smart energy device, a securitydevice, a solar panel or solar array, a municipal infrastructure devicecontrolling electric power (e.g., a smart grid), lighting, water, etc.;an industrial automation and enterprise device; a logistics controller;agricultural equipment; military defense equipment, vehicles, aircraft,ships, and weaponry, etc. Still further, a mobile apparatus may providefor connected medicine or telemedicine support, e.g., health care at adistance. Telehealth devices may include telehealth monitoring devicesand telehealth administration devices, whose communication may be givenpreferential treatment or prioritized access over other types ofinformation, e.g., in terms of prioritized access for transport ofcritical service data, and/or relevant QoS for transport of criticalservice data.

Wireless communication between a RAN 104 and a UE 106 may be describedas utilizing an air interface. Transmissions over the air interface froma base station (e.g., base station 108) to one or more UEs (e.g., UE106) may be referred to as downlink (DL) transmission. In accordancewith certain aspects of the present disclosure, the term downlink mayrefer to a point-to-multipoint transmission originating at a schedulingentity (described further below; e.g., base station 108). Another way todescribe this scheme may be to use the term broadcast channelmultiplexing. Transmissions from a UE (e.g., UE 106) to a base station(e.g., base station 108) may be referred to as uplink (UL)transmissions. In accordance with further aspects of the presentdisclosure, the term uplink may refer to a point-to-point transmissionoriginating at a scheduled entity (described further below; e.g., UE106).

In some examples, access to the air interface may be scheduled, whereina scheduling entity (e.g., a base station 108) allocates resources forcommunication among some or all devices and equipment within its servicearea or cell. Within the present disclosure, as discussed further below,the scheduling entity may be responsible for scheduling, assigning,reconfiguring, and releasing resources for one or more scheduledentities. That is, for scheduled communication, UEs 106, which may bescheduled entities, may utilize resources allocated by the schedulingentity 108.

Base stations 108 are not the only entities that may function asscheduling entities. That is, in some examples, a UE may function as ascheduling entity, scheduling resources for one or more scheduledentities (e.g., one or more other UEs).

As illustrated in FIG. 1, a scheduling entity 108 may broadcast downlinktraffic 112 to one or more scheduled entities 106. Broadly, thescheduling entity 108 is a node or device responsible for schedulingtraffic in a wireless communication network, including the downlinktraffic 112 and, in some examples, uplink traffic 116 from one or morescheduled entities 106 to the scheduling entity 108. On the other hand,the scheduled entity 106 is a node or device that receives downlinkcontrol information 114, including but not limited to schedulinginformation (e.g., a grant), synchronization or timing information, orother control information from another entity in the wirelesscommunication network such as the scheduling entity 108.

In general, base stations 108 may include a backhaul interface forcommunication with a backhaul portion 120 of the wireless communicationsystem. The backhaul 120 may provide a link between a base station 108and the core network 102. Further, in some examples, a backhaul networkmay provide interconnection between the respective base stations 108.Various types of backhaul interfaces may be employed, such as a directphysical connection, a virtual network, or the like using any suitabletransport network.

The core network 102 may be a part of the wireless communication system100, and may be independent of the radio access technology used in theRAN 104. In some examples, the core network 102 may be configuredaccording to 5G standards (e.g., 5GC). In other examples, the corenetwork 102 may be configured according to a 4G evolved packet core(EPC), or any other suitable standard or configuration.

Referring now to FIG. 2, by way of example and without limitation, aschematic illustration of a RAN 200 is provided. In some examples, theRAN 200 may be the same as the RAN 104 described above and illustratedin FIG. 1. The geographic area covered by the RAN 200 may be dividedinto cellular regions (cells) that can be uniquely identified by a userequipment (UE) based on an identification broadcasted from one accesspoint or base station. FIG. 2 illustrates macrocells 202, 204, and 206,and a small cell 208, each of which may include one or more sectors (notshown). A sector is a sub-area of a cell. All sectors within one cellare served by the same base station. A radio link within a sector can beidentified by a single logical identification belonging to that sector.In a cell that is divided into sectors, the multiple sectors within acell can be formed by groups of antennas with each antenna responsiblefor communication with UEs in a portion of the cell.

In FIG. 2, two base stations 210 and 212 are shown in cells 202 and 204;and a third base station 214 is shown controlling a remote radio head(RRH) 216 in cell 206. That is, a base station can have an integratedantenna or can be connected to an antenna or RRH by feeder cables. Inthe illustrated example, the cells 202, 204, and 126 may be referred toas macrocells, as the base stations 210, 212, and 214 support cellshaving a large size. Further, a base station 218 is shown in the smallcell 208 (e.g., a microcell, picocell, femtocell, home base station,home Node B, home eNode B, etc.) which may overlap with one or moremacrocells. In this example, the cell 208 may be referred to as a smallcell, as the base station 218 supports a cell having a relatively smallsize. Cell sizing can be done according to system design as well ascomponent constraints.

It is to be understood that the radio access network 200 may include anynumber of wireless base stations and cells. Further, a relay node may bedeployed to extend the size or coverage area of a given cell. The basestations 210, 212, 214, 218 provide wireless access points to a corenetwork for any number of mobile apparatuses. In some examples, the basestations 210, 212, 214, and/or 218 may be the same as the basestation/scheduling entity 108 described above and illustrated in FIG. 1.

FIG. 2 further includes a quadcopter or drone 220, which may beconfigured to function as a base station. That is, in some examples, acell may not necessarily be stationary, and the geographic area of thecell may move according to the location of a mobile base station such asthe quadcopter 220.

Within the RAN 200, the cells may include UEs that may be incommunication with one or more sectors of each cell. Further, each basestation 210, 212, 214, 218, and 220 may be configured to provide anaccess point to a core network 102 (see FIG. 1) for all the UEs in therespective cells. For example, UEs 222 and 224 may be in communicationwith base station 210; UEs 226 and 228 may be in communication with basestation 212; UEs 230 and 232 may be in communication with base station214 by way of RRH 216; UE 234 may be in communication with base station218; and UE 236 may be in communication with mobile base station 220. Insome examples, the UEs 222, 224, 226, 228, 230, 232, 234, 236, 238, 240,and/or 242 may be the same as the UE/scheduled entity 106 describedabove and illustrated in FIG. 1.

In some examples, a mobile network node (e.g., quadcopter 220) may beconfigured to function as a UE. For example, the quadcopter 220 mayoperate within cell 202 by communicating with base station 210.

In a further aspect of the RAN 200, sidelink signals may be used betweenUEs without necessarily relying on scheduling or control informationfrom a base station. For example, two or more UEs (e.g., UEs 226 and228) may communicate with each other using peer to peer (P2P) orsidelink signals 227 without relaying that communication through a basestation (e.g., base station 212). In a further example, UE 238 isillustrated communicating with UEs 240 and 242. Here, the UE 238 mayfunction as a scheduling entity or a primary sidelink device, and UEs240 and 242 may function as a scheduled entity or a non-primary (e.g.,secondary) sidelink device. In still another example, a UE may functionas a scheduling entity in a device-to-device (D2D), peer-to-peer (P2P),or vehicle-to-vehicle (V2V) network, and/or in a mesh network. In a meshnetwork example, UEs 240 and 242 may optionally communicate directlywith one another in addition to communicating with the scheduling entity238. Thus, in a wireless communication system with scheduled access totime-frequency resources and having a cellular configuration, a P2Pconfiguration, or a mesh configuration, a scheduling entity and one ormore scheduled entities may communicate utilizing the scheduledresources.

In the radio access network 200, the ability for a UE to communicatewhile moving, independent of its location, is referred to as mobility.The various physical channels between the UE and the radio accessnetwork are generally set up, maintained, and released under the controlof an access and mobility management function (AMF, not illustrated,part of the core network 102 in FIG. 1), which may include a securitycontext management function (SCMF) that manages the security context forboth the control plane and the user plane functionality, and a securityanchor function (SEAF) that performs authentication.

In various aspects of the disclosure, a radio access network 200 mayutilize DL-based mobility or UL-based mobility to enable mobility andhandovers (i.e., the transfer of a UE's connection from one radiochannel to another). In a network configured for DL-based mobility,during a call with a scheduling entity, or at any other time, a UE maymonitor various parameters of the signal from its serving cell as wellas various parameters of neighboring cells. Depending on the quality ofthese parameters, the UE may maintain communication with one or more ofthe neighboring cells. During this time, if the UE moves from one cellto another, or if signal quality from a neighboring cell exceeds thatfrom the serving cell for a given amount of time, the UE may undertake ahandoff or handover from the serving cell to the neighboring (target)cell. For example, UE 224 (illustrated as a vehicle, although anysuitable form of UE may be used) may move from the geographic areacorresponding to its serving cell 202 to the geographic areacorresponding to a neighbor cell 206. When the signal strength orquality from the neighbor cell 206 exceeds that of its serving cell 202for a given amount of time, the UE 224 may transmit a reporting messageto its serving base station 210 indicating this condition. In response,the UE 224 may receive a handover command, and the UE may undergo ahandover to the cell 206.

In a network configured for UL-based mobility, UL reference signals fromeach UE may be utilized by the network to select a serving cell for eachUE. In some examples, the base stations 210, 212, and 214/216 maybroadcast unified synchronization signals (e.g., unified PrimarySynchronization Signals (PSSs), unified Secondary SynchronizationSignals (SSSs) and unified Physical Broadcast Channels (PBCH)). The UEs222, 224, 226, 228, 230, and 232 may receive the unified synchronizationsignals, derive the carrier frequency and slot timing from thesynchronization signals, and in response to deriving timing, transmit anuplink pilot or reference signal. The uplink pilot signal transmitted bya UE (e.g., UE 224) may be concurrently received by two or more cells(e.g., base stations 210 and 214/216) within the radio access network200. Each of the cells may measure a strength of the pilot signal, andthe radio access network (e.g., one or more of the base stations 210 and214/216 and/or a central node within the core network) may determine aserving cell for the UE 224. As the UE 224 moves through the radioaccess network 200, the network may continue to monitor the uplink pilotsignal transmitted by the UE 224. When the signal strength or quality ofthe pilot signal measured by a neighboring cell exceeds that of thesignal strength or quality measured by the serving cell, the network 200may handover the UE 224 from the serving cell to the neighboring cell,with or without informing the UE 224.

Although the synchronization signal transmitted by the base stations210, 212, and 214/216 may be unified, the synchronization signal may notidentify a particular cell, but rather may identify a zone of multiplecells operating on the same frequency and/or with the same timing. Theuse of zones in 5G networks or other next generation communicationnetworks enables the uplink-based mobility framework and improves theefficiency of both the UE and the network, since the number of mobilitymessages that need to be exchanged between the UE and the network may bereduced.

In various implementations, the air interface in the radio accessnetwork 200 may utilize licensed spectrum, unlicensed spectrum, orshared spectrum. Licensed spectrum provides for exclusive use of aportion of the spectrum, generally by virtue of a mobile networkoperator purchasing a license from a government regulatory body.Unlicensed spectrum provides for shared use of a portion of the spectrumwithout need for a government-granted license. While compliance withsome technical rules is generally still required to access unlicensedspectrum, generally, any operator or device may gain access. Sharedspectrum may fall between licensed and unlicensed spectrum, whereintechnical rules or limitations may be required to access the spectrum,but the spectrum may still be shared by multiple operators and/ormultiple RATs. For example, the holder of a license for a portion oflicensed spectrum may provide licensed shared access (LSA) to share thatspectrum with other parties, e.g., with suitable licensee-determinedconditions to gain access.

FIG. 3 is a block diagram illustrating an example of a hardwareimplementation for a core network device 300 employing a processingsystem 314. In one example, the core network device 300 may be a serverconfigured to implement a policy control function (PCF) and/or an accessand mobility management function (AMF) as illustrated in FIGS. 5-7.

The core network device 300 may be implemented with a processing system314 that includes one or more processors 304. Examples of processors 304include microprocessors, microcontrollers, digital signal processors(DSPs), field programmable gate arrays (FPGAs), programmable logicdevices (PLDs), state machines, gated logic, discrete hardware circuits,and other suitable hardware configured to perform the variousfunctionality described throughout this disclosure. In various examples,the core network device 300 may be configured to perform any one or moreof the functions described herein. That is, the processor 304, asutilized in the core network device 300, may be used to implement anyone or more of the processes and procedures described below andillustrated in FIG. 17.

In this example, the processing system 314 may be implemented with a busarchitecture, represented generally by the bus 302. The bus 302 mayinclude any number of interconnecting buses and bridges depending on thespecific application of the processing system 314 and the overall designconstraints. The bus 302 communicatively couples together variouscircuits including one or more processors (represented generally by theprocessor 304), a memory 305, and computer-readable media (representedgenerally by the computer-readable medium 306). The bus 302 may alsolink various other circuits such as timing sources, peripherals, voltageregulators, and power management circuits, which are well known in theart, and therefore, will not be described any further. A bus interface308 provides an interface between the bus 302 and a transceiver 310. Thetransceiver 310 provides a communication interface or means forcommunicating with various other apparatus over a transmission medium.Depending upon the nature of the apparatus, a user interface 312 (e.g.,keypad, display, speaker, microphone, joystick) may also be provided. Ofcourse, such a user interface 312 is optional, and may be omitted insome examples, such as a base station.

In some aspects of the disclosure, the processor 304 may include aconnection establishing circuit 340 configured for various functions,including, for example, establishing a connection with a UE. Forexample, the connection establishing circuit 340 may be configured toimplement one or more of the functions described below in relation toFIG. 17, including, e.g., block 1702. The processor 304 may furtherinclude a message transmitting circuit 342 configured for variousfunctions, including, for example, transmitting, to the UE, a controlplane message, the control plane message including one or more types ofpolicy information if a size of the one or more types of policyinformation is less than or equal to a maximum payload size of thecontrol plane message, or information indicating at least a networklocation from where the one or more types of policy information may beobtained by the UE over a user plane if the size of the one or moretypes of policy information is greater than the maximum payload size ofthe control plane message. For example, the message transmitting circuit342 may be configured to implement one or more of the functionsdescribed below in relation to FIG. 13, including, e.g., block 1704.

The processor 304 is responsible for managing the bus 302 and generalprocessing, including the execution of software stored on thecomputer-readable medium 306. The software, when executed by theprocessor 304, causes the processing system 314 to perform the variousfunctions described below for any particular apparatus. Thecomputer-readable medium 306 and the memory 305 may also be used forstoring data that is manipulated by the processor 304 when executingsoftware.

One or more processors 304 in the processing system may executesoftware. Software shall be construed broadly to mean instructions,instruction sets, code, code segments, program code, programs,subprograms, software modules, applications, software applications,software packages, routines, subroutines, objects, executables, threadsof execution, procedures, functions, etc., whether referred to assoftware, firmware, middleware, microcode, hardware descriptionlanguage, or otherwise. The software may reside on a computer-readablemedium 306. The computer-readable medium 306 may be a non-transitorycomputer-readable medium. A non-transitory computer-readable mediumincludes, by way of example, a magnetic storage device (e.g., hard disk,floppy disk, magnetic strip), an optical disk (e.g., a compact disc (CD)or a digital versatile disc (DVD)), a smart card, a flash memory device(e.g., a card, a stick, or a key drive), a random access memory (RAM), aread only memory (ROM), a programmable ROM (PROM), an erasable PROM(EPROM), an electrically erasable PROM (EEPROM), a register, a removabledisk, and any other suitable medium for storing software and/orinstructions that may be accessed and read by a computer. Thecomputer-readable medium 306 may reside in the processing system 314,external to the processing system 314, or distributed across multipleentities including the processing system 314. The computer-readablemedium 306 may be embodied in a computer program product. By way ofexample, a computer program product may include a computer-readablemedium in packaging materials. Those skilled in the art will recognizehow best to implement the described functionality presented throughoutthis disclosure depending on the particular application and the overalldesign constraints imposed on the overall system.

In one or more examples, the computer-readable storage medium 306 mayinclude connection establishing software 352 configured for variousfunctions, including, for example, establishing a connection with a UE.For example, the connection establishing instructions 352 may beconfigured to implement one or more of the functions described herein inrelation to FIG. 17, including, e.g., block 1702. The computer-readablestorage medium 306 may further include message transmitting software 354configured for various functions, including, for example, transmitting,to the UE, a control plane message, the control plane message includingone or more types of policy information if a size of the one or moretypes of policy information is less than or equal to a maximum payloadsize of the control plane message, or information indicating at least anetwork location from where the one or more types of policy informationmay be obtained by the UE over a user plane if the size of the one ormore types of policy information is greater than the maximum payloadsize of the control plane message. For example, the message transmittinginstructions 354 may be configured to implement one or more of thefunctions described herein in relation to FIG. 17, including, e.g.,block 1704.

FIG. 4 is a conceptual diagram illustrating an example of a hardwareimplementation for an exemplary UE 400 employing a processing system414. In accordance with various aspects of the disclosure, an element,or any portion of an element, or any combination of elements may beimplemented with a processing system 414 that includes one or moreprocessors 404. For example, the UE 400 may be a UE as illustrated inany one or more of FIGS. 1, 2, 5, 6, and/or 7.

The processing system 414 may be substantially the same as theprocessing system 314 illustrated in FIG. 3, including a bus interface408, a bus 402, memory 405, a processor 404, and a computer-readablemedium 406. Furthermore, the UE 400 may include a user interface 412 anda transceiver 410 substantially similar to those described above in FIG.3. That is, the processor 404, as utilized in a UE 400, may be used toimplement any one or more of the processes described below andillustrated in FIGS. 14-16.

In some aspects of the disclosure, the processor 404 may include aconnection establishing circuit 440 configured for various functions,including, for example, establishing a connection to a network and/orestablishing a connection to a server based on a network locationpreconfigured at the UE 400. For example, the connection establishingcircuit 440 may be configured to implement one or more of the functionsdescribed below in relation to FIGS. 14-16, including, e.g., blocks1436, 1502 and 1602. The processor 404 may further include a messageobtaining circuit 442 configured for various functions, including, forexample, obtaining a control plane message from the network, where thecontrol plane message includes one or more types of policy informationif a size of the one or more types of policy information is less than orequal to a maximum payload size of the control plane message, orinformation indicating at least a network location from where the one ormore types of policy information may be obtained by the UE over a userplane if the size of the one or more types of policy information isgreater than the maximum payload size of the control plane message. Forexample, the message obtaining circuit 442 may also be configured toobtain a different PLMN/RAT list if an integrity verification (e.g., anintegrity verification of a control plane message including one or moretypes of policy information) is not successful, and/or to obtain one ormore types of policy information from a server (e.g. the core networkdevice 300). For example, the message obtaining circuit 442 may beconfigured to implement one or more of the functions described below inrelation to FIGS. 14-16, including, e.g., blocks 1404, 1424, 1436, 1504,1508, and 1604. The processor 404 may include a message integrityverifying circuit 444 configured for various functions, including, forexample, verifying an integrity of the contents of a control planemessage. For example, the message integrity verifying circuit 444 may beconfigured to implement one or more of the functions described below inrelation to FIG. 14-16, including, e.g., blocks 1406, 1408, and 1506.The processor 404 may include a policy updating circuit 446 configuredfor various functions, including, for example, updating at least onepolicy based on the one or more types of policy information. Forexample, the policy updating circuit 446 may be configured to implementone or more of the functions described below in relation to FIGS. 14-16,including, e.g., blocks 1414, 1416, 1426, 1428, 1510, and 1606.

In one or more examples, the computer-readable storage medium 406 mayinclude connection establishing software 452 configured for variousfunctions, including, for example, establishing a connection to anetwork and/or establishing a connection to a server based on a networklocation preconfigured at the UE 400. For example, the connectionestablishing software 452 may be configured to implement one or more ofthe functions described herein in relation to FIGS. 14-16, including,e.g., blocks 1436, 1502 and 1602.

In one or more examples, the computer-readable storage medium 406 mayinclude message obtaining software 454 configured for various functions,including, for example, obtaining a control plane message from thenetwork, where the control plane message includes one or more types ofpolicy information if a size of the one or more types of policyinformation is less than or equal to a maximum payload size of thecontrol plane message, or information indicating at least a networklocation from where the one or more types of policy information may beobtained by the UE over a user plane if the size of the one or moretypes of policy information is greater than the maximum payload size ofthe control plane message. For example, the message obtaining software454 may also be configured to obtain a different PLMN/RAT list if anintegrity verification (e.g., an integrity verification of a controlplane message including one or more types of policy information) is notsuccessful, and/or to obtain one or more types of policy informationfrom a server (e.g. the core network device 300). For example, themessage obtaining software 454 may be configured to implement one ormore of the functions described herein in relation to FIGS. 14-16,including, e.g., blocks 1404, 1424, 1436, 1504, 1508, and 1604.

In one or more examples, the computer-readable storage medium 406 mayinclude message integrity verifying software 456 configured for variousfunctions, including, for example, verifying an integrity of thecontents of a control plane message. For example, the message integrityverifying software 456 may be configured to implement one or more of thefunctions described below in relation to FIG. 14-16, including, e.g.,blocks 1406, 1408, and 1506.

In one or more examples, the computer-readable storage medium 406 mayinclude policy updating software 458 configured for various functions,including, for example, updating at least one policy based on the one ormore types of policy information. For example, the policy updatingsoftware 458 may be configured to implement one or more of the functionsdescribed herein in relation to FIGS. 14-16, including, e.g., blocks1414, 1416, 1426, 1428, 1510, and 1606.

FIG. 5 illustrates an example of a potential 5G system architecture 500(also referred to as system architecture 500) in service-based interfacerepresentation for a non-roaming scenario in accordance with variousaspects of the disclosure. As shown in FIG. 5, the system architecture500 includes a network slice selection function (NSSF) 502, a networkexposure function (NEF) 504, a network repository function (NRF) 506, apolicy control function (PCF) 508, a unified data management (UDM) 510,an application function (AF) 512, an authentication server function(AUSF) 514, an access and mobility management function (AMF) 516, asession management function (SMF) 518, a UE 520, a (radio) accessnetwork ((R)AN) 522, a user plane function (UPF) 524, and a data network(DN) 526. As further shown in FIG. 5, the NSSF 502, NEF 504, NRF 506,PCF 508, UDM 510, AF 512, AUSF 514, AMF 516, and the SMF 518 mayrespectively implement the Nnssf interface 528, Nnef interface 530, Nnrfinterface 532, Npcf interface 534, Nudm interface 536, Naf interface538, Nausf interface 540, Namf interface 542, and Nsmf interface 544.

As shown in FIG. 5, the UE 520 is in communication with (R)AN 522 viathe interface 552. In some aspects of the disclosure, the interface 552may be a new radio (NR) interface. In the system architecture 500, N1546 represents the reference point between the UE 520 and the AMF 516,N2 548 represents the reference point between the (R)AN 522 and the AMF516, N3 554 represents the reference point between the (R)AN 522 and theUPF 524, N4 550 represents the reference point between the SMF 518 andthe UPF 524, and N6 556 represents the reference point between the UPF524 and the DN 526.

In various aspects of the disclosure, the PCF 608 may support one ormore independent functions, such as supporting a unified policyframework to govern network behavior, providing policy rules to controlplane function(s) to enforce them, and/or accessing subscriptioninformation relevant for policy decisions in a unified data repository(UDR), and/or other appropriate functions as defined in 5G standards. Invarious aspects of the disclosure, the AMF 616 may support one or morefunctions, such as non-access stratum (NAS) ciphering and integrityprotection, registration management, connection management, reachabilitymanagement, mobility management, providing transport for sessionmanagement (SM) messages between the UE 626 and the SMF 618, transparentproxy for routing SM messages, access authentication and authorization,and/or other appropriate functions as defined in 5G standards. Invarious aspects of the disclosure, the SMF 618 may support one or morefunctions, such as session management (e.g. session establishment,modify and release, including maintaining a tunnel between the UPF 630and the (R)AN 628, UE IP address allocation & management, configuringtraffic steering at the UPF 630 to route traffic to proper destination,termination of interfaces towards policy control functions, chargingdata collection and support of charging interfaces, control andcoordination of charging data collection at the UPF 630, and/or otherappropriate functions as defined in 5G standards.

FIG. 6 illustrates an example of a potential 5G system architecture 600(also referred to as system architecture 600) in service-based interfacerepresentation for a roaming scenario in accordance with various aspectsof the disclosure. As shown in FIG. 6, the system architecture 600includes a visited public land mobile network (VPLMN) 672 and a homepublic land mobile network (HPLMN) 674. As shown in FIG. 6, the VPLMN672 includes NSSF 602, NEF 604, NRF 606, PCF 608 (also referred to as avisited PCF (vPCF) 608), AF 610, AMF 616, SMF 618, UE 626, (R)AN 628,UPF 630, and DN 632. As further shown in FIG. 6, the HPLMN 674 includesUDM 612, NRF 614, AUSF 620, PCF 622 (also referred to as a home PCF(hPCF) 622), and NEF 624. In the example configuration of FIG. 6, theNSSF 602, NEF 604, NRF 606, PCF 608, AF 610, UDM 612, NRF 614, AMF 616,SMF 618, AUSF 620, PCF 622, and NEF 624 may respectively implement theNnssf interface 634, Nnef interface 636, Nnrf interface 638, Npcfinterface 640, Naf interface 642, Nudm interface 644, Nnrf interface646, Namf interface 648, Nsmf interface 650, Nausf interface 652, Npcfinterface 654, and Nnef interface 656. In the system architecture 600,N1 658 represents the reference point between the UE 626 and the AMF616, N2 660 represents the reference point between the (R)AN 628 and theAMF 616, N3 668 represents the reference point between the (R)AN 628 andthe UPF 630, N4 662 represents the reference point between the SMF 618and the UPF 630, and N6 670 represents the reference point between theUPF 630 and the DN 632.

The UE 626 may be in communication with the (R)AN 628 via the interface664. In some aspects of the disclosure, the interface 664 may be a newradio (NR) interface. In the configuration of FIG. 6, it should be notedthat the UE 626 is outside of the HPLMN 674 and is roaming in the VPLMN672. In some aspects of the disclosure, the UE 626 in FIG. 6 maycorrespond to the UE 520 in FIG. 5.

FIG. 7 illustrates an example of a potential 5G system architecture 700(also referred to as system architecture 700) for a roaming scenario inaccordance with various aspects of the disclosure. It should be notedthat the system architecture 700 in FIG. 7 is a reference pointrepresentation of the previously described system architecture 600. Asshown in FIG. 7, the system architecture 700 includes the VPLMN 672 andthe HPLMN 674. As further shown in FIG. 7, the VPLMN 672 includes theNSSF 602, AMF 616, SMF 618, vPCF 608, AF 610, UE 626, (R)AN 628, UPF630, and DN 632. As further shown in FIG. 7, the HPLMN 674 includes theAUSF 620, UDM 612, and the hPCF 622. In the system architecture 700, N3752 represents the reference point between the (R)AN 628 and the UPF630, N5 746 represents the reference point between the vPCF 608 and theAF 610, N6 754 represents the reference point between the UPF 630 andthe DN 632, N7 736 represents the reference point between the SMF 618and the vPCF 608, N8 730 represents the reference point between the AMF616 and the UDM 612, N10 732 represents the reference point between theSMF 618 and the UDM 612, N11 734 represents the reference point betweenthe AMF 616 and the SMF 618, N12 728 represents the reference pointbetween the AMF 616 and the AUSF 620, N13 756 represents the referencepoint between the AUSF 620 and the UDM 612, N15 744 represents thereference point between the AMF 616 and the vPCF 608, N22 726 representsthe reference point between the NSSF 602 and the AMF 616, and N24 738represents the reference point between the vPCF 608 and the hPCF 622. Inthe aspects described herein, it should be noted that the term“reference point” may be used interchangeably with the term “interface.”

Some aspects of the disclosure are directed to solutions that enabledelivery of policy information (e.g., information regarding preferrednetworks and radio access technologies (RATs), UE route selection policy(URSP) information, and/or an access network discovery and selectionpolicy (ANDSP) information) from a PCF to a UE. Accordingly, some of thedescribed solutions enable an HPLMN (e.g., HPLMN 674) to provide one ormore of its roaming UEs (e.g., UE 626 in VPLMN 672) policy information(e.g., policy information provided by the hPCF 622) depending on thecurrent location of the one or more roaming UEs. In some aspects of thedisclosure, such solutions may be implemented with respect to thecontrol plane. For example, the HPLMN 674 may communicate informationregarding preferred networks and RATs to the UE 626 via the VPLMN 672using control plane signaling. In some aspects of the disclosure, theVPLMN 672 may not be able to alter the policy information provided bythe HPLMN 674.

Distribution of Policy Decisions

FIG. 8 illustrates an exemplary table 800 listing several types ofpolicy information that may be delivered to a UE (e.g., UE 520, 626) inaccordance with various aspects of the disclosure. As shown in FIG. 8,such types of policy information may include quality of service (QoS)information 802, packet inspection information 804, packet routing andforwarding information 806, traffic usage reporting information 808,traffic steering control information 810, congestion managementinformation 812, mobility and service area restriction information 814,RAT and/or frequency selection priority information 816, ANDSPinformation 818, and/or URSP information 820. The UE may use the ANDSPinformation 818 for selecting non-3GPP accesses (e.g., a wireless localarea network, such as a Wi-Fi network) and for deciding how to routetraffic between the selected 3GPP access and non-3GPP access. In someaspects of the disclosure, an hPCF (e.g., hPCF 622) or a vPCF (e.g.,vPCF 608) may provide the ANDSP information 818 to the UE via an AMF(e.g., AMF 616) when the UE is roaming. The UE (e.g., 520, 626) may usethe URSP information 820 to determine how to route outgoing traffic(e.g., to an existing PDU session, to a new PDU session, or offload tonon-3GPP access). The table 800 further shows the distribution of theenforcement of policy decisions, indicating the enforcement control partfunctions 822 per type of policy, their actual enforcement functions824, and the associated reference points/interfaces 826.

In some aspects of the disclosure, there may be a number of categoriesof policy information to be delivered to a UE. For example, a firstcategory of policy information may include policy information (alsoreferred to as PCF rules) that may be processed by an AMF (e.g., AMF516, 616) and/or an SMF (e.g., SMF 518, 618) before delivery to the UE(e.g., UE 520, 626). Such policy information may include the QoSinformation 802 and/or the service area restriction information 814. Forexample, a second category of policy information may include policyinformation that may be delivered transparently to the UE. Such policyinformation may include ANDSP information 818 and/or URSP information820. In some aspects of the disclosure, the first category of policyinformation may be handled as part of the mobility management (MM) andsession management (SM) signaling over NAS. With respect to the secondcategory of information, in some aspects of the disclosure, the AMF maybe configured to transparently deliver the URSP information 820 to theUE over the N1 interface (e.g., N1 interface 546, 658). In some aspectsof the disclosure, the AMF may also be configured to transparentlyprovide ANDSP information 818 to the UE over the N1 interface. In someaspects, the network architectures described herein (e.g., networkarchitectures 500, 600, 700) may implement a generic policy transportmechanism over the N1 interface to enable transparent delivery of theANDSP information 818 from the AMF to the UE over the N1 interface. Insome aspects, a Namf interface (e.g., Namf interface 542, 648) mayprovide a mechanism for a PCF (e.g., PCF 508, 608) to invoke thedelivery of policy information (e.g., ANDSP information 818 and/or URSPinformation 820) over the N1 interface (e.g., N1 interface 546, 658).

In some scenarios, delivery of policy information to the UE (e.g., UE520, 626) via the N1 interface (e.g., N1 interface 546, 658) may beunsuitable or inefficient in cases where the policy information (e.g.,ANDSP information 818) is too large. In such cases, if the size of thepolicy information exceeds a size limit for the NAS (e.g., a maximumsize of one NAS protocol data unit (PDU)), a hybrid delivery approachmay be used to deliver the policy information to the UE. Accordingly, insome aspects of the disclosure, a NAS control plane message (alsoreferred to as a control plane message) to the UE may trigger the UE toretrieve the policy information through a user plane connection. Thecontrol plane message may include a Uniform Resource Locator (URL) thatthe UE may access to retrieve the policy information.

Interactions between a Policy Control Function (PCF) and an Access andMobility Management Function (AMF)

In various aspects of the disclosure, the PCF (e.g., PCF 508, 608) maybe configured to provide access and mobility management related policiesto the AMF (e.g., AMF 516, 616). For example, the PCF may transmit theaccess and mobility management related policies via the Npcf interface(e.g., Npcf interface 534, 640), which may be received at the AMF viathe Namf (e.g., Namf interface 542, 648). In some aspects of thedisclosure, the Npcf and Namf interfaces may be configured to supportvarious features, such as handling of a UE context establishment requestsent by the AMF to the PCF as part of the registration procedure(s) ofthe UE, provisioning of an access and mobility management decision fromthe PCF to the AMF, delivery of network events from the AMF to the PCF,handling of UE context termination request sent by the AMF to the PCF aspart of a UE de-registration procedure, and handling of transparentdelivery of policy information for the UE or a policy download triggerfrom the PCF to the UE via the AMF.

Interactions between a Policy Control Function (PCF) and a UserEquipment (UE)

In some aspects of the disclosure, the Npcf interface (e.g., Npcfinterface 534, 640) and the Namf interface (e.g., Namf interface 542,648) may be configured to enable delivery of policy information to theUE (e.g., UE 520, 626). In one example approach, the PCF (e.g., PCF 508,608) may provide policy information via the Npcf interface to the AMF(e.g., AMF 516, 616). The AMF may receive the policy information via theNamf interface and may deliver the policy information to the UE over theN1 interface. As described above, the N1 interface (e.g., N1 interface546, 658) represents the reference point between the UE and the AMF andrepresents interactions that are transparently transmitted over the(R)AN. With reference to the non-roaming scenario shown in FIG. 5, forexample, the PCF 508 may provide the URSP information 820 to the AMF 516(e.g., via the Npcf interface 534 and the Namf interface 542). The AMF516 may then provide the URSP information 820 to the UE 520 via the N1interface 546. In some aspects of the disclosure, the AMF 516 may notchange the URSP information 820 provided by PCF 508. In another example,with reference to the roaming scenario shown in FIG. 7, the vPCF 608 mayprovide the URSP information 820 to the AMF 616 (e.g., via the N15interface 744). The AMF 616 may then provide the URSP information 820 tothe UE 626 via the N1 interface 658. In this example, the URSPinformation 820 provided to the UE 626 may contain information providedby the hPCF 622 and information provided by the vPCF 608.

In another example approach, the Npcf and Namf may be configured toenable delivery of a policy download trigger from the PCF to the UE viathe AMF. This approach may be used if the policy information to bedelivered to the UE exceeds a threshold. For example, if the PCF (e.g.,PCF 508, 608) determines that the size of the policy information to bedelivered to the UE (e.g., UE 520, 626) exceeds the threshold (e.g.where the threshold is set to the maximum size of a NAS PDU), the PCFmay transmit a policy download trigger that is intended for the UE viathe Npcf interface (e.g., Npcf interface 534, 640) to the AMF (e.g., AMF516, 616). The AMF may receive the policy download trigger via the Namfinterface (e.g., Namf interface 542, 648) and may deliver the policydownload trigger to the UE over the N1 interface (e.g., N1 interface546, 658). The UE, in response to the policy download trigger, maydownload policy information at a URL. In some aspects, and as describedin greater detail herein, the policy download trigger may be configuredas a PCF payload that includes the URL.

Example Options for Delivering Policy Information to the UE

In a first example option for delivering policy information to the UE,with reference to the roaming scenario shown in FIG. 6, the vPCF 608 inthe VPLMN 672 may deliver policy information to the UE 626 using ageneric UE configuration update procedure. This option, however, may notbe suitable for certain types of policy information because contents ofa configuration update command may be set by the AMF 616 in the VPLMN672. This may allow the VPLMN 672 to modify the policy information. Insome cases, this option may be suitable for communication of datamanaged by the AMF 616.

In a second example option for delivering policy information to the UE,with reference to the non-roaming scenario in FIG. 5, the PCF 508 maydeliver policy information to the UE 520 by transmitting a policydownload trigger to the UE 520. The policy download trigger may be anon-access stratum (NAS) control plane message that causes the UE 520 toset up an IP connection (e.g., a secure IP connection) to a server andto obtain the policy information over the user plane. This option may beused in cases where the size of the policy information is expected to bemore than the payload of one NAS control plane payload. In some aspects,the PCF 508 may implement this option by generating a dedicated NAScontrol plane message (e.g., a “Policy Download Trigger message”). Inother aspects, the PCF 508 may implement this option by using a genericNAS transport message with a new payload type field (e.g., a “PolicyDownload Trigger” payload type field). In a roaming scenario, withreference to FIG. 6, the vPCF 608 in the VPLMN 672 may deliver policyinformation to the UE 626 by transmitting a policy download trigger tothe UE 626 in cases where the size of the policy information is expectedto be more than the payload of one NAS control plane payload. Aspreviously described, the policy download trigger may be a NAS controlplane message that causes the UE 626 to set up an IP connection (e.g., asecure IP connection) to a server and to obtain the policy informationfrom the server over the user plane. In some aspects, the VPLMN 672 mayimplement this option by generating a dedicated NAS control planemessage (e.g., a “Policy Download Trigger message”). In other aspects,the VPLMN 672 may implement this option by using a generic NAS transportmessage with a new payload type field (e.g., a “Policy Download Trigger”payload type field).

In a third example option for delivering policy information to the UE,with reference to the non-roaming scenario in FIG. 5, the PCF 508 maydeliver policy information to the UE 520 in a NAS control plane message.In some aspects, the PCF 508 may implement this option by generating adedicated NAS control plane message (e.g. a “Policy Update” message). Inother aspects, the PCF 508 may implement this option by using a genericNAS transport message with a new payload type field (e.g., a “PolicyUpdate” payload type field). In a roaming scenario, with reference toFIG. 6, the vPCF 608 in the VPLMN 672 may deliver policy information tothe UE 626 in a NAS control plane message. In some aspects, the vPCF 608in the VPLMN 672 may implement this option by creating a dedicated NAScontrol plane message (e.g. a “Policy Update” message). In otheraspects, the vPCF 608 in the VPLMN 672 may implement this option byusing a generic NAS transport message with a new payload type field(e.g., a “Policy Update” payload type field).

In a fourth example option for delivering policy information to the UE,with reference to the non-roaming scenario in FIG. 5, the PCF 508 maydeliver QoS policy information 802 to the UE 520 by providing policyinformation to the SMF 518 via the Npcf interface 534. The SMF 518 mayreceive the policy information via the Nsmf interface 544. The SMF 518may prepare the QoS rules based on the received policy information andmay deliver the QoS rules to the UE 520 in a PDU session establishmentmessage.

In a fifth example option for delivering policy information to the UE,with reference to the non-roaming scenario in FIG. 5, the PCF 508 maydeliver mobility restrictions (MOD) and/or service area restrictions 814to the AMF 516 via the Npcf interface 534. The AMF 516 may receive themobility restrictions (MOD) and/or service area restrictions via theNamf interface 542. In some aspects of the disclosure, the AMF 516 maydetermine the mobility restriction parameters based on the policyinformation received from the PCF 508 over an interface (e.g., aninterface N15 that may be configured between the AMF 516 and the PCF508) and may deliver the mobility restriction parameters to the UE 520in a configuration update message or a registration accept message.

In conventional network architectures, a unified, extensible solutionfor communicating all types of policy information (e.g. preferred publicland mobile network (PLMN)/radio access technologies (RATs) list, ANDSP,URSP) to a UE may not be available because the size of one or morepolicies may exceed the maximum length (e.g., 65,535 octets) of a singleNAS transport message payload. For example, the size of a preferredPLMN/RAT list may be within the maximum length of a single NAS transportmessage payload, but the sizes of the ANDSP information 818 and the URSPinformation 820 may exceed the maximum length of a single NAS transportmessage payload. As such, in some scenarios, all types of policyinformation (e.g. preferred PLMN/RATs list, ANDSP, URSP) may not beincluded in a single NAS transport message payload. These limitationsmay be overcome by implementing the sixth example option for deliveringpolicy information to the UE described herein.

In a sixth example option for delivering policy information to the UE,if the size of the policy information to be delivered to the UE is lessthan or equal to the maximum length of the payload container informationelement (IE) (e.g., policy information ≤65,535 octets) of a generic NAStransport message, a generic NAS transport message may be used with thepayload container IE set to the actual policy information. For example,the PCF 508 may transmit a transparent PCF payload that includes thepolicy information to the AMF 516 via the Npcf interface 534. The AMF516 may receive the PCF payload via the Namf interface 542. The AMF 516may then encapsulate the PCF payload in a NAS transport message and maydeliver the NAS transport message to the UE 520 via the N1 interface546. However, if the size of the policy information is greater than themaximum length of the payload container IE (e.g., policyinformation >65,535 octets) of a generic NAS transport message, the PCF508 may transmit a transparent PCF payload to the AMF 516 via the Npcfinterface 534. The PCF payload may include an indication of the policyto be updated, an indication that the PCF payload includes a URL, andthe URL that may be accessed by the UE 520 to retrieve the policyinformation. The AMF 516 may receive the PCF payload via the Namfinterface 542. The AMF 516 may then encapsulate the PCF payload in a NAStransport message and may deliver the NAS transport message to the UE520 via the N1 interface 546. The UE 520 may access the URL in theencapsulated PCF payload to obtain the policy information over the userplane.

In a roaming scenario, with reference to FIG. 6, if the size of thepolicy information is less than or equal to the maximum length of thepayload container information element (IE) (e.g., policy information≤65,535 octets) of a generic NAS transport message, a generic NAStransport message may be used with the payload container IE set to theactual policy information. For example, the vPCF 608 may transmit atransparent PCF payload that includes the policy information to the AMF616 via the Npcf interface 640. The AMF 616 may receive the PCF payloadvia the Namf interface 648. The AMF 616 may then encapsulate the PCFpayload in a NAS transport message and may deliver the NAS transportmessage to the UE 626 via the N1 interface 658. However, if the size ofthe policy information is greater than the maximum length of the payloadcontainer IE (e.g., policy information >65,535 octets) of a generic NAStransport message, the PCF 608 may transmit a transparent PCF payload tothe AMF 616 via the Npcf interface 640. The PCF payload may include anindication of the policy to be updated, an indication that the PCFpayload includes a URL, and the URL that may be accessed by the UE 520to retrieve the policy information. The AMF 616 may receive the PCFpayload via the Namf interface 648. The AMF 616 may then encapsulate thePCF payload in a NAS transport message and may deliver the NAS transportmessage to the UE 626 via the N1 interface 658. In some aspects, thetransparent payload from the vPCF 608 may include policy informationprovided by the hPCF 622 in the HPLMN 674. In various aspects of thedisclosure, and as described in detail herein, the payload informationIE may indicate a type of policy that is being conveyed and/or whetherthe payload container IE contains the actual policy data or a URL.

As described in detail herein, the disclosed aspects may enable thenetwork to “push” a policy information update to the UE (e.g., 520,626). In other aspects of the disclosure, a UE (e.g., 520, 626) may“pull” (e.g., request) updated policy information from the network. Forexample, to enable the UE (e.g., 520, 626) to pull updated policyinformation, the UE may be pre-configured with a URL and may connect tothe URL anytime to download a policy information update over the userplane. In some aspects of the disclosure, the UE (e.g., 520, 626) may beconfigured by the home operator with the IP address of the PCF (e.g.,PCF 508, 608, 622) and may access the IP address to download the policyinformation. In other aspects of the disclosure, the UE (e.g., 520, 626)may discover the IP address of the PCF (e.g., PCF 508, 608, 622) when inthe HPLMN (e.g., HPLMN 674) or when roaming in a VPLMN (e.g., VPLMN 672)using a standardized URL or a fully qualified domain name (FQDN). Insome aspects of the disclosure, the serving PLMN (e.g., the VPLMN 672)may also provide the URL or FQDN used to discover the PCF (e.g., vPCF608) upon successful registration.

FIG. 9 illustrates an example of the contents in a downlink (DL) NAStransport message for delivering policy information, such as a preferredPLMN/RAT list update, to a UE (e.g., UE 520, 626) in accordance withvarious aspects of the disclosure. As shown in FIG. 9, the DL NAStransport message contents 900 may include a number of informationelements (IEs) 914, such as an extended protocol discriminator 902, asecurity header type 904, a spare half octet 906, a DL NAS transportmessage identity 908, a payload container 910, and payload information912. The attributes listed under the type field 916 generally indicatethe type of the corresponding information element. In the exampleconfiguration of FIG. 9, the attribute value “M” under the presencefield 918 indicates that the corresponding information element ismandatory in the DL NAS transport message. In the example configurationof FIG. 9, the attribute value “V” under the format field 920 meansvalue only, whereas the attribute values “TLV” and “TLV-E” under theformat field 920 mean type, length, and value. In the exampleconfiguration of FIG. 9, each attribute value under the length field 922indicates the length of the corresponding information element in termsof octets. For example, the attribute value “1” indicated under thelength field 922 for the DL NAS transport message identity 908 meansthat the length of the DL NAS transport message identity 908 may be oneoctet. As another example, the attribute value “4-65,538” indicatedunder the length field 922 for the payload container 910 means that thelength of the payload container 910 may be between 4 to 65,538 octets.

FIG. 10 shows an example payload information IE structure 1000 that maybe used to update one or more policies at the UE (e.g., UE 520, 626). Inthe example shown in FIG. 10, the payload information IE structure 1000may include the payload information IE indicator (IEI) 1002 (e.g., octet1 in FIG. 10), the length of payload information contents 1004 (e.g.,octet 2 in FIG. 10), the payload information type (e.g., octet 3 in FIG.10) 1006, the download type 1008 (e.g., octet 4, bit 5 to bit 8 in FIG.10), and the policy type 1010 (e.g., octet 4, bit 1 to bit 4 in FIG.10).

FIG. 11 shows an example coding 1100 of payload information type bitsfor the payload information IE structure 1000. It should be understoodthat the example illustrated in FIG. 11 represents one possible formatthat may be used for a NAS transport message, and within the scope ofthe present disclosure, many other suitable message formats may beutilized. As shown in FIG. 11, different payload information types maybe indicated using different codes (e.g., different 8-bit binary codes).For example, as shown in FIG. 11, the 8-bit binary code “00000011” maybe used to indicate a Short Message Service (SMS) payload informationtype 1102 and the 8-bit binary code “00000101” may be used to indicate apolicy update payload information type 1104. For example, with referenceto FIGS. 10 and 11, the network may set the payload information type1006 in FIG. 10 to indicate that the payload information type is apolicy update payload information type 1104 by setting the eight bits inoctet 3 in FIG. 10 to “00000101.”

FIG. 12 shows an example coding 1200 of policy type bits for the payloadinformation IE structure 1000. It should be understood that the exampleillustrated in FIG. 12 represents one possible format that may be usedfor a NAS transport message, and within the scope of the presentdisclosure, many other suitable message formats may be utilized. Asshown in FIG. 12, different policy types may be indicated usingdifferent codes (e.g., different 4-bit binary codes). For example, asshown in FIG. 12, the 4-bit binary code “0001” may be used to indicate apreferred PLMN/RATs list policy type 1202, the 4-bit binary code “0010”may be used to indicate an ANDSP policy type 1204, and the 4-bit binarycode “0011” may be used to indicate a URSP policy type 1206. Forexample, with reference to FIGS. 10 and 12, the network may set thepolicy type 1010 in FIG. 10 to indicate that the policy type is theANDSP policy type 1204 by setting the four bits in octet 4 (e.g., bit 1to bit 4) in FIG. 10 to “0010.”

FIG. 13 shows an example coding 1300 of download type bits for thepayload information IE structure 1000. It should be understood that theexample illustrated in FIG. 13 represents one possible format that maybe used for a NAS transport message, and within the scope of the presentdisclosure, many other suitable message formats may be utilized. Asshown in FIG. 13, different download types may be indicated usingdifferent codes (e.g., different 4-bit binary codes). For example, asshown in FIG. 13, the 4-bit binary code “0001” may be used to indicate acontrol plane download type 1302 and the 4-bit binary code “0010” may beused to indicate a user plane download type 1304. For example, withreference to FIGS. 10 and 13, the network may set the download type 1008in FIG. 10 to indicate that the download type is the user plane downloadtype 1304 by setting the four bits in octet 4 (e.g., bit 5 to bit 8) inFIG. 10 to “0010.”

Procedures for Steering the UE in the VPLMN

FIG. 14 (including FIGS. 14A to 14D) is a flow chart illustrating anexemplary process for steering the UE 626 in the VPLMN 672 according tosome aspects of the disclosure. The purpose of the procedure forsteering the UE 626 in the VPLMN 672 is to allow the HPLMN 674 to updatethe list of preferred public land mobile network (PLMN)/radio accesstechnologies (RATs) at the UE 626 (e.g., depending on the currentlocation of the UE 626) using NAS signaling. It should be understoodthat blocks with dashed lines in FIG. 14 represent optional blocks.

In the aspects described with reference to FIG. 14, the VPLMN 672 maynot be able to modify policy information provided by the HPLMN 674. TheUE 626 may be configured to maintain a separate steering attempt counterfor each PLMN. The UE 626 may increment the steering attempt counter fora given PLMN if an integrity check of the contents of the payloadcontainer IE of a DL NAS transport message fails at the UE 626, wherethe DL NAS transport message includes a payload information IEcontaining a payload information type field indicating that the payloadcontainer contains an updated list of preferred PLMN/RATs. The UE 626may reset the steering attempt counter if any one of the followingconditions is met: 1) the UE 626 is switched off; 2) the UniversalSubscriber Identity Module (USIM) of the UE 626 is removed; and 3) theintegrity check of the contents of the payload container IE of a DL NAStransport message with a payload information IE containing a payloadinformation type field indicating that the payload container contains anupdated list of preferred PLMN/RATs passes at the UE 626.

At block 1402, the UE 626 may roam to a VPLMN 672 (e.g., the UE 626 mayleave an area covered by the HPLMN 674 and may enter an area covered bythe VPLMN 672). At block 1404, the UE 626 may obtain, in the VPLMN 672,a DL NAS transport message that includes a payload container informationelement (IE). At least a portion of the payload container IE may beprovided by the HPLMN 674 of the UE 626, and the at least a portion ofthe payload container IE may include an updated preferred PLMN/RATs listor a network location from where the updated PLMN/RATs list may beobtained by the UE.

In one aspect of the disclosure, if the length of the updated preferredPLMN/RATs list to be provided to the UE 626 is less than or equal to themaximum length of a single NAS transport message payload (e.g., lessthan or equal to 65,535 octets), the VPLMN 672 may transmit a DL NAStransport message to the UE 626 where: 1) the payload container IE ofthe DL NAS transport message is set to include the updated list ofpreferred PLMN/RATs; and 2) the payload information IE of the DL NAStransport message is set to include a payload information type fieldindicating that the payload container contains an updated list ofpreferred PLMN/RATs, and is further set to include a MAC field enablingthe UE 626 to verify the integrity of the contents of the payloadcontainer. In some aspects of the disclosure, the updated list ofpreferred PLMN/RATs may be encoded (e.g., compressed and/or encrypted).In such aspects, the previously described length of the updated list ofpreferred PLMN/RATs may refer to the encoded length of the updated listof preferred PLMN/RATs.

In another aspect of the disclosure, if the length of the updated listof preferred PLMN/RATs is greater than the maximum length of a singleNAS transport message payload (e.g., greater than 65,535 octets), theVPLMN 672 may transmit a DL NAS transport message to the UE 626where: 1) the payload container IE of the DL NAS transport message isset to include a URL that the UE 626 may use to retrieve the updatedlist of preferred PLMN/RATs over the user plane; and 2) the payloadinformation IE of the DL NAS transport message is set to include apayload information type field indicating that the payload containercontains a URL to retrieve an updated list of preferred PLMN/RATs overthe user plane, and is further set to include a MAC field enabling theUE 626 to verify the integrity of the contents of the payload container.

At block 1406, after the UE has obtained the DL NAS transport message,the UE 1406 may perform an integrity check on the contents of the DL NAStransport message. For example, the UE 626 may attempt to verify theintegrity of the contents in the payload container IE using the MACfield in the payload information IE. If the integrity check of thecontents in the payload container IE is successful (e.g., the integritycheck passes), then at block 1410, the UE 626 may reset the steeringattempt counter for the registered PLMN (e.g., the VPLMN 672). If theintegrity check of the contents in the payload container IE issuccessful (e.g., at block 1406) and if the payload information typefield of the DL NAS transport message indicates that the payloadcontainer IE contains an updated list of preferred PLMN/RATs (e.g., atblock 1412), then at block 1414, the UE 626 may replace the highestpriority entries in a PLMN selection list (e.g., an Operator ControlledPLMN Selector with Access Technology list) stored in the UE 626 with theupdated list of preferred PLMN/RATs included in the payload container IEof the DL NAS transport message. At block 1416, the UE 626 may deletethe PLMNs identified by the list in the payload container IE of the DLNAS transport message from a forbidden PLMN list, if the PLMNsidentified by the list in the payload container IE are present inforbidden PLMN list. In some aspects, the UE 626 may further delete anyinformation associated with the deleted PLMNs that may be stored in theUSIM and/or the internal memory of the UE 626. At block 1418, the UE 626may take the information in the updated list of preferred PLMN/RATs intoaccount in subsequent attempts to access a higher priority PLMN. Atblock 1420, the UE 626 may attempt to obtain service on a higherpriority PLMN by acting as if a timer T that controls periodic attemptshas expired.

With reference to block 1408, if the integrity check of the contents inthe payload container IE is successful and if the payload informationtype field of the DL NAS transport message indicates that at least aportion of the payload container IE contains a network location (e.g., aURL) from where the updated list of preferred PLMN/RATs may be obtainedby the UE over the user plane (e.g., at block 1422), then at block 1424,the UE 626 may obtain the updated list of preferred PLMN/RATs over theuser plane using the URL included in the payload container IE. At block1426, the UE 626 may replace the highest priority entries in a PLMNselection list (e.g., an Operator Controlled PLMN Selector with AccessTechnology list) stored in the UE 626 with the list of preferredPLMN/RATs obtained over the user plane. At block 1428, the UE 626 maydelete the PLMNs identified by the obtained list of preferred PLMN/RATsfrom a forbidden PLMN list, if the PLMNs identified by the obtained listof preferred PLMN/RATs are present in forbidden PLMN list. In someaspects, the UE 626 may further delete any information associated withthe deleted PLMNs that may be stored in the USIM and/or the internalmemory of the UE 626. At block 1430, the UE 626 may take the informationin the updated list of preferred PLMN/RATs into account in subsequentattempts to access a higher priority PLMN. At block 1432, the UE 626 mayattempt to obtain service on a higher priority PLMN by acting as if atimer T that controls periodic attempts has expired. If at least aportion of the payload container IE of the DL NAS transport message doesnot contain a network location (e.g., a URL) from where the updated listof preferred PLMN/RATs may be obtained by the UE over the user plane(e.g., at block 1422), then the process returns to block 1404.

With reference to block 1408, if the integrity check of the contents ofthe payload container IE fails at the UE 626, then at block 1434, the UE626 may increment the steering attempt counter for the registered PLMN(e.g., the VPLMN 672). At block 1436, if a network location (e.g., aURL) for obtaining an updated list of preferred PLMN/RATs is availableat the UE 626 (e.g., if the UE 626 is pre-configured with a URL), the UE626 may obtain the list over the user plane using that URL. At block1438, if no URL for obtaining an updated list of preferred PLMN/RATs isavailable to the UE 626 (e.g., if the UE 626 is not pre-configured witha URL) and the steering attempt counter is less than a threshold (e.g.,a threshold set to five attempts), the UE 626 may transmit a UL NAStransport message with: 1) a payload container IE containing the PLMN IDof the registered PLMN and the value of the steering attempt counter forthe registered PLMN; and 2) a payload information IE containing apayload information type field indicating that the payload containercontains information related to the failure of steering the UE 626 inthe VPLMN 672. At block 1440, if no URL for obtaining an updated list ofpreferred PLMN/RATs is available to the UE 626 (e.g., if the UE 626 isnot pre-configured with a URL) and the steering attempt counter is equalto the threshold (e.g., a threshold set to five attempts), the UE 626may add the registered PLMN (e.g., the VPLMN 672) to the forbidden PLMNslist and may perform a PLMN selection procedure.

FIG. 15 is a flow chart illustrating an exemplary process 1500 foroperating a UE in accordance with some aspects of the presentdisclosure. It should be understood that blocks with dashed lines inFIG. 15 represent optional blocks. As described below, some or allillustrated features may be omitted in a particular implementationwithin the scope of the present disclosure, and some illustratedfeatures may not be required for implementation of all embodiments. Insome examples, the process 1500 may be carried out by the UE 400illustrated in FIG. 4. In some examples, the process 1500 may be carriedout by any suitable apparatus or means for carrying out the functions oralgorithm described below.

At block 1502, the UE establishes a connection to a network. At block1504, the UE obtains a control plane message from the network, thecontrol plane message including one or more types of policy informationif a size of the one or more types of policy information is less than orequal to a maximum payload size of the control plane message, orinformation indicating at least a network location from where the one ormore types of policy information may be obtained by the UE over a userplane if the size of the one or more types of policy information isgreater than the maximum payload size of the control plane message. Atblock 1506, the UE optionally verifies an integrity of the contents ofthe control plane message. At block 1508, the UE optionally obtains adifferent PLMN/RAT list if the verification (e.g., integrityverification) is not successful. At block 1510, the UE optionallyupdates at least one policy based on the one or more types of policyinformation. In some aspects, the UE optionally updates at least onepolicy based on the one or more types of policy information if theverification (e.g., integrity verification) is successful.

FIG. 16 is a flow chart illustrating an exemplary process 1600 foroperating a UE in accordance with some aspects of the presentdisclosure. It should be understood that blocks with dashed lines inFIG. 16 represent optional blocks. As described below, some or allillustrated features may be omitted in a particular implementationwithin the scope of the present disclosure, and some illustratedfeatures may not be required for implementation of all embodiments. Insome examples, the process 1600 may be carried out by the UE 400illustrated in FIG. 4. In some examples, the process 1600 may be carriedout by any suitable apparatus or means for carrying out the functions oralgorithm described below.

At block 1602, the UE establishes a connection to a server based on anetwork location preconfigured at the UE. In some aspects, the servermay be the core network device 300. At block 1604, the UE obtains one ormore types of policy information from the server. At block 1606, the UEoptionally updates at least one policy based on the obtained one or moretypes of policy information.

FIG. 17 is a flow chart illustrating an exemplary process 1700 foroperating a core network device in accordance with some aspects of thepresent disclosure. As described below, some or all illustrated featuresmay be omitted in a particular implementation within the scope of thepresent disclosure, and some illustrated features may not be requiredfor implementation of all embodiments. In some examples, the process1700 may be carried out by the core network device 300 illustrated inFIG. 3. In some examples, the process 1700 may be carried out by anysuitable apparatus or means for carrying out the functions or algorithmdescribed below.

At block 1702, the core network device establishes a connection with aUE. At block 1704, the core network device transmits, to the UE, acontrol plane message, the control plane message including one or moretypes of policy information if a size of the one or more types of policyinformation is less than or equal to a maximum payload size of thecontrol plane message, or information indicating at least a networklocation from where the one or more types of policy information may beobtained by the UE over a user plane if the size of the one or moretypes of policy information is greater than the maximum payload size ofthe control plane message.

In one configuration, the apparatus 300 for wireless communicationincludes means for establishing a connection with a user equipment andmeans for transmitting, to the UE, a control plane message, the controlplane message including one or more types of policy information if asize of the one or more types of policy information is less than orequal to a maximum payload size of the control plane message, orinformation indicating at least a network location from where the one ormore types of policy information may be obtained by the UE over a userplane if the size of the one or more types of policy information isgreater than the maximum payload size of the control plane message. Inone aspect, the aforementioned means may be the processor(s) 304configured to perform the functions recited by the aforementioned means.In another aspect, the aforementioned means may be a circuit or anyapparatus configured to perform the functions recited by theaforementioned means.

Of course, in the above examples, the circuitry included in theprocessor 304 is merely provided as an example, and other means forcarrying out the described functions may be included within variousaspects of the present disclosure, including but not limited to theinstructions stored in the computer-readable storage medium 306, or anyother suitable apparatus or means described in any one of the FIGS. 1,2, and/or 3, and utilizing, for example, the processes and/or algorithmsdescribed herein in relation to FIG. 17.

In one configuration, the apparatus 400 for wireless communicationincludes means for establishing a connection to a network, means forobtaining a control plane message from the network, the control planemessage including one or more types of policy information if a size ofthe one or more types of policy information is less than or equal to amaximum payload size of the control plane message, or informationindicating at least a network location from where the one or more typesof policy information may be obtained by the UE over a user plane if thesize of the one or more types of policy information is greater than themaximum payload size of the control plane message, means for verifyingan integrity of the contents of the control plane message, means forupdating at least one policy based on the one or more types of policyinformation, means for obtaining a different PLMN/RAT list if theverification is not successful. In one aspect, the aforementioned meansmay be the processor(s) 404 configured to perform the functions recitedby the aforementioned means. In another aspect, the aforementioned meansmay be a circuit or any apparatus configured to perform the functionsrecited by the aforementioned means.

Of course, in the above examples, the circuitry included in theprocessor 404 is merely provided as an example, and other means forcarrying out the described functions may be included within variousaspects of the present disclosure, including but not limited to theinstructions stored in the computer-readable storage medium 406, or anyother suitable apparatus or means described in any one of the FIGS. 1,2, and/or 4, and utilizing, for example, the processes and/or algorithmsdescribed herein in relation to FIGS. 14-16.

Several aspects of a wireless communication network have been presentedwith reference to an exemplary implementation. As those skilled in theart will readily appreciate, various aspects described throughout thisdisclosure may be extended to other telecommunication systems, networkarchitectures and communication standards.

By way of example, various aspects may be implemented within othersystems defined by 3GPP, such as Long-Term Evolution (LTE), the EvolvedPacket System (EPS), the Universal Mobile Telecommunication System(UMTS), and/or the Global System for Mobile (GSM). Various aspects mayalso be extended to systems defined by the 3rd Generation PartnershipProject 2 (3GPP2), such as CDMA2000 and/or Evolution-Data Optimized(EV-DO). Other examples may be implemented within systems employing IEEE802.11 (Wi-Fi), IEEE 802.16 (WiMAX), IEEE 802.20, Ultra-Wideband (UWB),Bluetooth, and/or other suitable systems. The actual telecommunicationstandard, network architecture, and/or communication standard employedwill depend on the specific application and the overall designconstraints imposed on the system.

Within the present disclosure, the word “exemplary” is used to mean“serving as an example, instance, or illustration.” Any implementationor aspect described herein as “exemplary” is not necessarily to beconstrued as preferred or advantageous over other aspects of thedisclosure. Likewise, the term “aspects” does not require that allaspects of the disclosure include the discussed feature, advantage ormode of operation. The term “coupled” is used herein to refer to thedirect or indirect coupling between two objects. For example, if objectA physically touches object B, and object B touches object C, thenobjects A and C may still be considered coupled to one another—even ifthey do not directly physically touch each other. For instance, a firstobject may be coupled to a second object even though the first object isnever directly physically in contact with the second object. The terms“circuit” and “circuitry” are used broadly, and intended to include bothhardware implementations of electrical devices and conductors that, whenconnected and configured, enable the performance of the functionsdescribed in the present disclosure, without limitation as to the typeof electronic circuits, as well as software implementations ofinformation and instructions that, when executed by a processor, enablethe performance of the functions described in the present disclosure. Asused herein, the term “obtaining” may include one or more actionsincluding, but not limited to, receiving, acquiring, determining, or anycombination thereof.

One or more of the components, steps, features and/or functionsillustrated in FIGS. 1-17 may be rearranged and/or combined into asingle component, step, feature or function or embodied in severalcomponents, steps, or functions. Additional elements, components, steps,and/or functions may also be added without departing from novel featuresdisclosed herein. The apparatus, devices, and/or components illustratedin FIGS. 1-17 may be configured to perform one or more of the methods,features, or steps described herein. The novel algorithms describedherein may also be efficiently implemented in software and/or embeddedin hardware.

It is to be understood that the specific order or hierarchy of steps inthe methods disclosed is an illustration of exemplary processes. Basedupon design preferences, it is understood that the specific order orhierarchy of steps in the methods may be rearranged. The accompanyingmethod claims present elements of the various steps in a sample order,and are not meant to be limited to the specific order or hierarchypresented unless specifically recited therein.

The previous description is provided to enable any person skilled in theart to practice the various aspects described herein. Variousmodifications to these aspects will be readily apparent to those skilledin the art, and the generic principles defined herein may be applied toother aspects. Thus, the claims are not intended to be limited to theaspects shown herein, but are to be accorded the full scope consistentwith the language of the claims, wherein reference to an element in thesingular is not intended to mean “one and only one” unless specificallyso stated, but rather “one or more.” Unless specifically statedotherwise, the term “some” refers to one or more. A phrase referring to“at least one of” a list of items refers to any combination of thoseitems, including single members. As an example, “at least one of: a, b,or c” is intended to cover: a; b; c; a and b; a and c; b and c; and a, band c. All structural and functional equivalents to the elements of thevarious aspects described throughout this disclosure that are known orlater come to be known to those of ordinary skill in the art areexpressly incorporated herein by reference and are intended to beencompassed by the claims. Moreover, nothing disclosed herein isintended to be dedicated to the public regardless of whether suchdisclosure is explicitly recited in the claims. No claim element is tobe construed under the provisions of 35 U.S.C. § 112(f) unless theelement is expressly recited using the phrase “means for” or, in thecase of a method claim, the element is recited using the phrase “stepfor.”

What is claimed is:
 1. A method of wireless communication, comprising:preconfiguring a user equipment (UE) with an internet protocol (IP)address of a policy control function (PCF); establishing, at the UE, aconnection to the PCF based on the IP address of the PCF preconfiguredat the UE; obtaining, by the UE, one or more types of policy informationdirectly from the PCF using the IP address of the PCF; and updating, atthe UE, at least one policy based on the obtained one or more types ofpolicy information.
 2. The method of claim 1, wherein the UE isconfigured to update the at least one policy if the UE is roaming in avisited home public land mobile network (VPLMN).
 3. The method of claim1, wherein the one or more types of policy information comprises apublic land mobile network (PLMN)/radio access technologies (RATs) list,a UE route selection policy (URSP), an access network discovery andselection policy (ANDSP), one or more mobility restrictions, a qualityof service (QoS) policy, or some combination thereof.
 4. The method ofclaim 1, wherein the one or more types of policy information is obtainedfrom the PCF over a user plane.
 5. The method of claim 1, wherein theconnection comprises an Internet Protocol (IP) connection.
 6. Anapparatus for wireless communication with a network, the apparatus beinga user equipment (UE) and comprising: a processor; a transceivercommunicatively coupled to the processor; and a memory communicativelycoupled to the processor, wherein the processor is configured to:preconfigure the apparatus with an internet protocol (IP) address of apolicy control function (PCF); establish a connection to the PCF basedon the IP address of the PCF preconfigured at the apparatus; obtain oneor more types of policy information directly from the PCF using the IPaddress of the PCF; and update at least one policy based on the obtainedone or more types of policy information.
 7. The apparatus of claim 6,wherein the processor is configured to update the at least one policy ifthe apparatus is roaming in a visited home public land mobile network(VPLMN).
 8. The apparatus of claim 6, wherein the one or more types ofpolicy information comprises a public land mobile network (PLMN)/radioaccess technologies (RATs) list, a UE route selection policy (URSP), anaccess network discovery and selection policy (ANDSP), one or moremobility restrictions, a quality of service (QoS) policy, or somecombination thereof.
 9. The apparatus of claim 6, wherein the one ormore types of policy information is obtained from the PCF over a userplane.
 10. The apparatus of claim 6, wherein the connection comprises anInternet Protocol (IP) connection.
 11. An apparatus for wirelesscommunication, the apparatus being a user equipment (UE) and comprising:means for preconfiguring the apparatus with an internet protocol (IP)address of a policy control function (PCF); means for establishing aconnection to the PCF based on the IP address of the PCF preconfiguredat the apparatus; means for obtaining one or more types of policyinformation directly from the PCF using the IP address of the PCF; andmeans for updating at least one policy based on the obtained one or moretypes of policy information.
 12. The apparatus of claim 11, wherein theapparatus is configured to update the at least one policy if theapparatus is roaming in a visited home public land mobile network(VPLMN).
 13. The apparatus of claim 11, wherein the one or more types ofpolicy information comprises a public land mobile network (PLMN)/radioaccess technologies (RATs) list, a UE route selection policy (URSP), anaccess network discovery and selection policy (ANDSP), one or moremobility restrictions, a quality of service (QoS) policy, or somecombination thereof.
 14. The apparatus of claim 11, wherein the one ormore types of policy information is obtained from the PCF over a userplane.
 15. The apparatus of claim 11, wherein the connection comprisesan Internet Protocol (IP) connection.
 16. An article of manufacture foruse by a user equipment (UE) in a wireless communication network, thearticle comprising: a non-transitory computer-readable medium havingstored therein instructions executable by one or more processors of theUE to: preconfigure the UE with an internet protocol (IP) address of apolicy control function (PCF); establish, at a user equipment (UE), aconnection to the PCF based on the IP address of the PCF preconfiguredat the UE; obtain, by the UE, one or more types of policy informationdirectly from the PCF using the IP address of the PCF; and update, atthe UE, at least one policy based on the obtained one or more types ofpolicy information.
 17. The article of manufacture of claim 16, whereinthe instructions are further executable by the one or more processors toupdate the at least one policy if the UE is roaming in a visited homepublic land mobile network (VPLMN).
 18. The article of manufacture ofclaim 16, wherein the one or more types of policy information comprisesa public land mobile network (PLMN)/radio access technologies (RATs)list, a UE route selection policy (URSP), an access network discoveryand selection policy (ANDSP), one or more mobility restrictions, aquality of service (QoS) policy, or some combination thereof.
 19. Thearticle of manufacture of claim 16, wherein the one or more types ofpolicy information is obtained from the PCF over a user plane.
 20. Thearticle of manufacture of claim 16, wherein the connection comprises anInternet Protocol (IP) connection.